mitigate device timing side channels #25

thestinger · 2017-05-15T05:06:15Z

No description provided.

thestinger · 2017-05-16T23:39:09Z

This is implemented.

Commit 4f350c6 (kvm: nVMX: Handle deferred early VMLAUNCH/VMRESUME failure properly) can result in L1(run kvm-unit-tests/run_tests.sh vmx_controls in L1) null pointer deference and also L0 calltrace when EPT=0 on both L0 and L1. In L1: BUG: unable to handle kernel paging request at ffffffffc015bf8f IP: vmx_vcpu_run+0x202/0x510 [kvm_intel] PGD 146e13067 P4D 146e13067 PUD 146e15067 PMD 3d2686067 PTE 3d4af9161 Oops: 0003 [GrapheneOS#1] PREEMPT SMP CPU: 2 PID: 1798 Comm: qemu-system-x86 Not tainted 4.14.0-rc4+ GrapheneOS#6 RIP: 0010:vmx_vcpu_run+0x202/0x510 [kvm_intel] Call Trace: WARNING: kernel stack frame pointer at ffffb86f4988bc18 in qemu-system-x86:1798 has bad value 0000000000000002 In L0: -----------[ cut here ]------------ WARNING: CPU: 6 PID: 4460 at /home/kernel/linux/arch/x86/kvm//vmx.c:9845 vmx_inject_page_fault_nested+0x130/0x140 [kvm_intel] CPU: 6 PID: 4460 Comm: qemu-system-x86 Tainted: G OE 4.14.0-rc7+ GrapheneOS#25 RIP: 0010:vmx_inject_page_fault_nested+0x130/0x140 [kvm_intel] Call Trace: paging64_page_fault+0x500/0xde0 [kvm] ? paging32_gva_to_gpa_nested+0x120/0x120 [kvm] ? nonpaging_page_fault+0x3b0/0x3b0 [kvm] ? __asan_storeN+0x12/0x20 ? paging64_gva_to_gpa+0xb0/0x120 [kvm] ? paging64_walk_addr_generic+0x11a0/0x11a0 [kvm] ? lock_acquire+0x2c0/0x2c0 ? vmx_read_guest_seg_ar+0x97/0x100 [kvm_intel] ? vmx_get_segment+0x2a6/0x310 [kvm_intel] ? sched_clock+0x1f/0x30 ? check_chain_key+0x137/0x1e0 ? __lock_acquire+0x83c/0x2420 ? kvm_multiple_exception+0xf2/0x220 [kvm] ? debug_check_no_locks_freed+0x240/0x240 ? debug_smp_processor_id+0x17/0x20 ? __lock_is_held+0x9e/0x100 kvm_mmu_page_fault+0x90/0x180 [kvm] kvm_handle_page_fault+0x15c/0x310 [kvm] ? __lock_is_held+0x9e/0x100 handle_exception+0x3c7/0x4d0 [kvm_intel] vmx_handle_exit+0x103/0x1010 [kvm_intel] ? kvm_arch_vcpu_ioctl_run+0x1628/0x2e20 [kvm] The commit avoids to load host state of vmcs12 as vmcs01's guest state since vmcs12 is not modified (except for the VM-instruction error field) if the checking of vmcs control area fails. However, the mmu context is switched to nested mmu in prepare_vmcs02() and it will not be reloaded since load_vmcs12_host_state() is skipped when nested VMLAUNCH/VMRESUME fails. This patch fixes it by reloading mmu context when nested VMLAUNCH/VMRESUME fails. Reviewed-by: Jim Mattson <[email protected]> Reviewed-by: Krish Sadhukhan <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Radim Krčmář <[email protected]> Cc: Jim Mattson <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> Reviewed-by: Paolo Bonzini <[email protected]> Signed-off-by: Radim Krčmář <[email protected]>

commit af3ff80 upstream. Because the HMAC template didn't check that its underlying hash algorithm is unkeyed, trying to use "hmac(hmac(sha3-512-generic))" through AF_ALG or through KEYCTL_DH_COMPUTE resulted in the inner HMAC being used without having been keyed, resulting in sha3_update() being called without sha3_init(), causing a stack buffer overflow. This is a very old bug, but it seems to have only started causing real problems when SHA-3 support was added (requires CONFIG_CRYPTO_SHA3) because the innermost hash's state is ->import()ed from a zeroed buffer, and it just so happens that other hash algorithms are fine with that, but SHA-3 is not. However, there could be arch or hardware-dependent hash algorithms also affected; I couldn't test everything. Fix the bug by introducing a function crypto_shash_alg_has_setkey() which tests whether a shash algorithm is keyed. Then update the HMAC template to require that its underlying hash algorithm is unkeyed. Here is a reproducer: #include <linux/if_alg.h> #include <sys/socket.h> int main() { int algfd; struct sockaddr_alg addr = { .salg_type = "hash", .salg_name = "hmac(hmac(sha3-512-generic))", }; char key[4096] = { 0 }; algfd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(algfd, (const struct sockaddr *)&addr, sizeof(addr)); setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key)); } Here was the KASAN report from syzbot: BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:341 [inline] BUG: KASAN: stack-out-of-bounds in sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 Write of size 4096 at addr ffff8801cca07c40 by task syzkaller076574/3044 CPU: 1 PID: 3044 Comm: syzkaller076574 Not tainted 4.14.0-mm1+ #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:341 [inline] sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 crypto_shash_update+0xcb/0x220 crypto/shash.c:109 shash_finup_unaligned+0x2a/0x60 crypto/shash.c:151 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 hmac_finup+0x182/0x330 crypto/hmac.c:152 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 shash_digest_unaligned+0x9e/0xd0 crypto/shash.c:172 crypto_shash_digest+0xc4/0x120 crypto/shash.c:186 hmac_setkey+0x36a/0x690 crypto/hmac.c:66 crypto_shash_setkey+0xad/0x190 crypto/shash.c:64 shash_async_setkey+0x47/0x60 crypto/shash.c:207 crypto_ahash_setkey+0xaf/0x180 crypto/ahash.c:200 hash_setkey+0x40/0x90 crypto/algif_hash.c:446 alg_setkey crypto/af_alg.c:221 [inline] alg_setsockopt+0x2a1/0x350 crypto/af_alg.c:254 SYSC_setsockopt net/socket.c:1851 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1830 entry_SYSCALL_64_fastpath+0x1f/0x96 Reported-by: syzbot <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Herbert Xu <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

Because the HMAC template didn't check that its underlying hash algorithm is unkeyed, trying to use "hmac(hmac(sha3-512-generic))" through AF_ALG or through KEYCTL_DH_COMPUTE resulted in the inner HMAC being used without having been keyed, resulting in sha3_update() being called without sha3_init(), causing a stack buffer overflow. This is a very old bug, but it seems to have only started causing real problems when SHA-3 support was added (requires CONFIG_CRYPTO_SHA3) because the innermost hash's state is ->import()ed from a zeroed buffer, and it just so happens that other hash algorithms are fine with that, but SHA-3 is not. However, there could be arch or hardware-dependent hash algorithms also affected; I couldn't test everything. Fix the bug by introducing a function crypto_shash_alg_has_setkey() which tests whether a shash algorithm is keyed. Then update the HMAC template to require that its underlying hash algorithm is unkeyed. Here is a reproducer: #include <linux/if_alg.h> #include <sys/socket.h> int main() { int algfd; struct sockaddr_alg addr = { .salg_type = "hash", .salg_name = "hmac(hmac(sha3-512-generic))", }; char key[4096] = { 0 }; algfd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(algfd, (const struct sockaddr *)&addr, sizeof(addr)); setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key)); } Here was the KASAN report from syzbot: BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:341 [inline] BUG: KASAN: stack-out-of-bounds in sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 Write of size 4096 at addr ffff8801cca07c40 by task syzkaller076574/3044 CPU: 1 PID: 3044 Comm: syzkaller076574 Not tainted 4.14.0-mm1+ GrapheneOS#25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:341 [inline] sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 crypto_shash_update+0xcb/0x220 crypto/shash.c:109 shash_finup_unaligned+0x2a/0x60 crypto/shash.c:151 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 hmac_finup+0x182/0x330 crypto/hmac.c:152 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 shash_digest_unaligned+0x9e/0xd0 crypto/shash.c:172 crypto_shash_digest+0xc4/0x120 crypto/shash.c:186 hmac_setkey+0x36a/0x690 crypto/hmac.c:66 crypto_shash_setkey+0xad/0x190 crypto/shash.c:64 shash_async_setkey+0x47/0x60 crypto/shash.c:207 crypto_ahash_setkey+0xaf/0x180 crypto/ahash.c:200 hash_setkey+0x40/0x90 crypto/algif_hash.c:446 alg_setkey crypto/af_alg.c:221 [inline] alg_setsockopt+0x2a1/0x350 crypto/af_alg.c:254 SYSC_setsockopt net/socket.c:1851 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1830 entry_SYSCALL_64_fastpath+0x1f/0x96 Reported-by: syzbot <[email protected]> Cc: <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Herbert Xu <[email protected]>

[ Upstream commit 5af4157 ] Commit 4f350c6 (kvm: nVMX: Handle deferred early VMLAUNCH/VMRESUME failure properly) can result in L1(run kvm-unit-tests/run_tests.sh vmx_controls in L1) null pointer deference and also L0 calltrace when EPT=0 on both L0 and L1. In L1: BUG: unable to handle kernel paging request at ffffffffc015bf8f IP: vmx_vcpu_run+0x202/0x510 [kvm_intel] PGD 146e13067 P4D 146e13067 PUD 146e15067 PMD 3d2686067 PTE 3d4af9161 Oops: 0003 [#1] PREEMPT SMP CPU: 2 PID: 1798 Comm: qemu-system-x86 Not tainted 4.14.0-rc4+ #6 RIP: 0010:vmx_vcpu_run+0x202/0x510 [kvm_intel] Call Trace: WARNING: kernel stack frame pointer at ffffb86f4988bc18 in qemu-system-x86:1798 has bad value 0000000000000002 In L0: -----------[ cut here ]------------ WARNING: CPU: 6 PID: 4460 at /home/kernel/linux/arch/x86/kvm//vmx.c:9845 vmx_inject_page_fault_nested+0x130/0x140 [kvm_intel] CPU: 6 PID: 4460 Comm: qemu-system-x86 Tainted: G OE 4.14.0-rc7+ #25 RIP: 0010:vmx_inject_page_fault_nested+0x130/0x140 [kvm_intel] Call Trace: paging64_page_fault+0x500/0xde0 [kvm] ? paging32_gva_to_gpa_nested+0x120/0x120 [kvm] ? nonpaging_page_fault+0x3b0/0x3b0 [kvm] ? __asan_storeN+0x12/0x20 ? paging64_gva_to_gpa+0xb0/0x120 [kvm] ? paging64_walk_addr_generic+0x11a0/0x11a0 [kvm] ? lock_acquire+0x2c0/0x2c0 ? vmx_read_guest_seg_ar+0x97/0x100 [kvm_intel] ? vmx_get_segment+0x2a6/0x310 [kvm_intel] ? sched_clock+0x1f/0x30 ? check_chain_key+0x137/0x1e0 ? __lock_acquire+0x83c/0x2420 ? kvm_multiple_exception+0xf2/0x220 [kvm] ? debug_check_no_locks_freed+0x240/0x240 ? debug_smp_processor_id+0x17/0x20 ? __lock_is_held+0x9e/0x100 kvm_mmu_page_fault+0x90/0x180 [kvm] kvm_handle_page_fault+0x15c/0x310 [kvm] ? __lock_is_held+0x9e/0x100 handle_exception+0x3c7/0x4d0 [kvm_intel] vmx_handle_exit+0x103/0x1010 [kvm_intel] ? kvm_arch_vcpu_ioctl_run+0x1628/0x2e20 [kvm] The commit avoids to load host state of vmcs12 as vmcs01's guest state since vmcs12 is not modified (except for the VM-instruction error field) if the checking of vmcs control area fails. However, the mmu context is switched to nested mmu in prepare_vmcs02() and it will not be reloaded since load_vmcs12_host_state() is skipped when nested VMLAUNCH/VMRESUME fails. This patch fixes it by reloading mmu context when nested VMLAUNCH/VMRESUME fails. Reviewed-by: Jim Mattson <[email protected]> Reviewed-by: Krish Sadhukhan <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Radim Krčmář <[email protected]> Cc: Jim Mattson <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> Reviewed-by: Paolo Bonzini <[email protected]> Signed-off-by: Radim Krčmář <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit af50e4b ] syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread #32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <[email protected]> Cc: Jiri Benc <[email protected]> Reported-by: syzbot <[email protected]> Acked-by: Jiri Benc <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit d50d82f upstream. In kernel 4.17 I removed some code from dm-bufio that did slab cache merging (commit 21bb132: "dm bufio: remove code that merges slab caches") - both slab and slub support merging caches with identical attributes, so dm-bufio now just calls kmem_cache_create and relies on implicit merging. This uncovered a bug in the slub subsystem - if we delete a cache and immediatelly create another cache with the same attributes, it fails because of duplicate filename in /sys/kernel/slab/. The slub subsystem offloads freeing the cache to a workqueue - and if we create the new cache before the workqueue runs, it complains because of duplicate filename in sysfs. This patch fixes the bug by moving the call of kobject_del from sysfs_slab_remove_workfn to shutdown_cache. kobject_del must be called while we hold slab_mutex - so that the sysfs entry is deleted before a cache with the same attributes could be created. Running device-mapper-test-suite with: dmtest run --suite thin-provisioning -n /commit_failure_causes_fallback/ triggered: Buffer I/O error on dev dm-0, logical block 1572848, async page read device-mapper: thin: 253:1: metadata operation 'dm_pool_alloc_data_block' failed: error = -5 device-mapper: thin: 253:1: aborting current metadata transaction sysfs: cannot create duplicate filename '/kernel/slab/:a-0000144' CPU: 2 PID: 1037 Comm: kworker/u48:1 Not tainted 4.17.0.snitm+ #25 Hardware name: Supermicro SYS-1029P-WTR/X11DDW-L, BIOS 2.0a 12/06/2017 Workqueue: dm-thin do_worker [dm_thin_pool] Call Trace: dump_stack+0x5a/0x73 sysfs_warn_dup+0x58/0x70 sysfs_create_dir_ns+0x77/0x80 kobject_add_internal+0xba/0x2e0 kobject_init_and_add+0x70/0xb0 sysfs_slab_add+0xb1/0x250 __kmem_cache_create+0x116/0x150 create_cache+0xd9/0x1f0 kmem_cache_create_usercopy+0x1c1/0x250 kmem_cache_create+0x18/0x20 dm_bufio_client_create+0x1ae/0x410 [dm_bufio] dm_block_manager_create+0x5e/0x90 [dm_persistent_data] __create_persistent_data_objects+0x38/0x940 [dm_thin_pool] dm_pool_abort_metadata+0x64/0x90 [dm_thin_pool] metadata_operation_failed+0x59/0x100 [dm_thin_pool] alloc_data_block.isra.53+0x86/0x180 [dm_thin_pool] process_cell+0x2a3/0x550 [dm_thin_pool] do_worker+0x28d/0x8f0 [dm_thin_pool] process_one_work+0x171/0x370 worker_thread+0x49/0x3f0 kthread+0xf8/0x130 ret_from_fork+0x35/0x40 kobject_add_internal failed for :a-0000144 with -EEXIST, don't try to register things with the same name in the same directory. kmem_cache_create(dm_bufio_buffer-16) failed with error -17 Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1806151817130.6333@file01.intranet.prod.int.rdu2.redhat.com Signed-off-by: Mikulas Patocka <[email protected]> Reported-by: Mike Snitzer <[email protected]> Tested-by: Mike Snitzer <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 36eb8ff upstream. Crash dump shows following instructions crash> bt PID: 0 TASK: ffffffffbe412480 CPU: 0 COMMAND: "swapper/0" #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1 #1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2 #2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c #3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a #4 [ffff891ee00039e0] no_context at ffffffffbd074643 #5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e #6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64 #7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a #8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8 #9 [ffff891ee0003b50] page_fault at ffffffffbda01925 [exception RIP: qlt_schedule_sess_for_deletion+15] RIP: ffffffffc02e526f RSP: ffff891ee0003c08 RFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffc0307847 RDX: 00000000000020e6 RSI: ffff891edbc377c8 RDI: 0000000000000000 RBP: ffff891ee0003c18 R8: ffffffffc02f0b20 R9: 0000000000000250 R10: 0000000000000258 R11: 000000000000b780 R12: ffff891ed9b43000 R13: 00000000000000f0 R14: 0000000000000006 R15: ffff891edbc377c8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx] #11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx] #12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx] #13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx] #14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59 #15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02 #16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90 #17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984 #18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5 #19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18 --- <IRQ stack> --- #20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e [exception RIP: unknown or invalid address] RIP: 000000000000001f RSP: 0000000000000000 RFLAGS: fff3b8c2091ebb3f RAX: ffffbba5a0000200 RBX: 0000be8cdfa8f9fa RCX: 0000000000000018 RDX: 0000000000000101 RSI: 000000000000015d RDI: 0000000000000193 RBP: 0000000000000083 R8: ffffffffbe403e38 R9: 0000000000000002 R10: 0000000000000000 R11: ffffffffbe56b820 R12: ffff891ee001cf00 R13: ffffffffbd11c0a4 R14: ffffffffbe403d60 R15: 0000000000000001 ORIG_RAX: ffff891ee0022ac0 CS: 0000 SS: ffffffffffffffb9 bt: WARNING: possibly bogus exception frame #21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd #22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907 #23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3 #24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42 #25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3 #26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa #27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca #28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675 #29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb #30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5 Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login") Cc: <[email protected]> # v4.17+ Signed-off-by: Chuck Anderson <[email protected]> Signed-off-by: Himanshu Madhani <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit d85536c ] Add missing prepare/unprepare operations for fbi->clk, this fixes following kernel warning: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at drivers/clk/clk.c:874 clk_core_enable+0x2c/0x1b0 Enabling unprepared disp0_clk Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 4.18.0-rc8-00032-g02b43ddd4f21-dirty #25 Hardware name: Marvell MMP2 (Device Tree Support) [<c010f7cc>] (unwind_backtrace) from [<c010cc6c>] (show_stack+0x10/0x14) [<c010cc6c>] (show_stack) from [<c011dab4>] (__warn+0xd8/0xf0) [<c011dab4>] (__warn) from [<c011db10>] (warn_slowpath_fmt+0x44/0x6c) [<c011db10>] (warn_slowpath_fmt) from [<c043898c>] (clk_core_enable+0x2c/0x1b0) [<c043898c>] (clk_core_enable) from [<c0439ec8>] (clk_core_enable_lock+0x18/0x2c) [<c0439ec8>] (clk_core_enable_lock) from [<c0436698>] (pxa168fb_probe+0x464/0x6ac) [<c0436698>] (pxa168fb_probe) from [<c04779a0>] (platform_drv_probe+0x48/0x94) [<c04779a0>] (platform_drv_probe) from [<c0475bec>] (driver_probe_device+0x328/0x470) [<c0475bec>] (driver_probe_device) from [<c0475de4>] (__driver_attach+0xb0/0x124) [<c0475de4>] (__driver_attach) from [<c0473c38>] (bus_for_each_dev+0x64/0xa0) [<c0473c38>] (bus_for_each_dev) from [<c0474ee0>] (bus_add_driver+0x1b8/0x230) [<c0474ee0>] (bus_add_driver) from [<c0476a20>] (driver_register+0xac/0xf0) [<c0476a20>] (driver_register) from [<c0102dd4>] (do_one_initcall+0xb8/0x1f0) [<c0102dd4>] (do_one_initcall) from [<c0b010a0>] (kernel_init_freeable+0x294/0x2e0) [<c0b010a0>] (kernel_init_freeable) from [<c07e9eb8>] (kernel_init+0x8/0x10c) [<c07e9eb8>] (kernel_init) from [<c01010e8>] (ret_from_fork+0x14/0x2c) Exception stack(0xd008bfb0 to 0xd008bff8) bfa0: 00000000 00000000 00000000 00000000 bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 ---[ end trace c0af40f9e2ed7cb4 ]--- Signed-off-by: Lubomir Rintel <[email protected]> [b.zolnierkie: enhance patch description a bit] Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

Increase kasan instrumented kernel stack size from 32k to 64k. Other architectures seems to get away with just doubling kernel stack size under kasan, but on s390 this appears to be not enough due to bigger frame size. The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting stack overflow is fs sync on xfs filesystem: #0 [9a0681e8] 704 bytes check_usage at 34b1fc GrapheneOS#1 [9a0684a8] 432 bytes check_usage at 34c710 GrapheneOS#2 [9a068658] 1048 bytes validate_chain at 35044a GrapheneOS#3 [9a068a70] 312 bytes __lock_acquire at 3559fe GrapheneOS#4 [9a068ba8] 440 bytes lock_acquire at 3576ee GrapheneOS#5 [9a068d60] 104 bytes _raw_spin_lock at 21b44e0 GrapheneOS#6 [9a068dc8] 1992 bytes enqueue_entity at 2dbf72 GrapheneOS#7 [9a069590] 1496 bytes enqueue_task_fair at 2df5f0 GrapheneOS#8 [9a069b68] 64 bytes ttwu_do_activate at 28f438 GrapheneOS#9 [9a069ba8] 552 bytes try_to_wake_up at 298c4c GrapheneOS#10 [9a069dd0] 168 bytes wake_up_worker at 23f97c GrapheneOS#11 [9a069e78] 200 bytes insert_work at 23fc2e GrapheneOS#12 [9a069f40] 648 bytes __queue_work at 2487c0 GrapheneOS#13 [9a06a1c8] 200 bytes __queue_delayed_work at 24db28 GrapheneOS#14 [9a06a290] 248 bytes mod_delayed_work_on at 24de84 GrapheneOS#15 [9a06a388] 24 bytes kblockd_mod_delayed_work_on at 153e2a0 GrapheneOS#16 [9a06a3a0] 288 bytes __blk_mq_delay_run_hw_queue at 158168c GrapheneOS#17 [9a06a4c0] 192 bytes blk_mq_run_hw_queue at 1581a3c GrapheneOS#18 [9a06a580] 184 bytes blk_mq_sched_insert_requests at 15a2192 GrapheneOS#19 [9a06a638] 1024 bytes blk_mq_flush_plug_list at 1590f3a GrapheneOS#20 [9a06aa38] 704 bytes blk_flush_plug_list at 1555028 GrapheneOS#21 [9a06acf8] 320 bytes schedule at 219e476 GrapheneOS#22 [9a06ae38] 760 bytes schedule_timeout at 21b0aac GrapheneOS#23 [9a06b130] 408 bytes wait_for_common at 21a1706 GrapheneOS#24 [9a06b2c8] 360 bytes xfs_buf_iowait at fa1540 GrapheneOS#25 [9a06b430] 256 bytes __xfs_buf_submit at fadae6 GrapheneOS#26 [9a06b530] 264 bytes xfs_buf_read_map at fae3f6 GrapheneOS#27 [9a06b638] 656 bytes xfs_trans_read_buf_map at 10ac9a8 GrapheneOS#28 [9a06b8c8] 304 bytes xfs_btree_kill_root at e72426 GrapheneOS#29 [9a06b9f8] 288 bytes xfs_btree_lookup_get_block at e7bc5e GrapheneOS#30 [9a06bb18] 624 bytes xfs_btree_lookup at e7e1a6 GrapheneOS#31 [9a06bd88] 2664 bytes xfs_alloc_ag_vextent_near at dfa070 GrapheneOS#32 [9a06c7f0] 144 bytes xfs_alloc_ag_vextent at dff3ca GrapheneOS#33 [9a06c880] 1128 bytes xfs_alloc_vextent at e05fce GrapheneOS#34 [9a06cce8] 584 bytes xfs_bmap_btalloc at e58342 GrapheneOS#35 [9a06cf30] 1336 bytes xfs_bmapi_write at e618de GrapheneOS#36 [9a06d468] 776 bytes xfs_iomap_write_allocate at ff678e GrapheneOS#37 [9a06d770] 720 bytes xfs_map_blocks at f82af8 GrapheneOS#38 [9a06da40] 928 bytes xfs_writepage_map at f83cd6 GrapheneOS#39 [9a06dde0] 320 bytes xfs_do_writepage at f85872 GrapheneOS#40 [9a06df20] 1320 bytes write_cache_pages at 73dfe8 GrapheneOS#41 [9a06e448] 208 bytes xfs_vm_writepages at f7f892 GrapheneOS#42 [9a06e518] 88 bytes do_writepages at 73fe6a GrapheneOS#43 [9a06e570] 872 bytes __writeback_single_inode at a20cb6 GrapheneOS#44 [9a06e8d8] 664 bytes writeback_sb_inodes at a23be2 GrapheneOS#45 [9a06eb70] 296 bytes __writeback_inodes_wb at a242e0 GrapheneOS#46 [9a06ec98] 928 bytes wb_writeback at a2500e GrapheneOS#47 [9a06f038] 848 bytes wb_do_writeback at a260ae GrapheneOS#48 [9a06f388] 536 bytes wb_workfn at a28228 GrapheneOS#49 [9a06f5a0] 1088 bytes process_one_work at 24a234 GrapheneOS#50 [9a06f9e0] 1120 bytes worker_thread at 24ba26 GrapheneOS#51 [9a06fe40] 104 bytes kthread at 26545a GrapheneOS#52 [9a06fea8] kernel_thread_starter at 21b6b62 To be able to increase the stack size to 64k reuse LLILL instruction in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE (65192) value as unsigned. Reported-by: Benjamin Block <[email protected]> Reviewed-by: Heiko Carstens <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]>

create_ctx can be called from atomic context, hence use GFP_ATOMIC instead of GFP_KERNEL. [ 395.962599] BUG: sleeping function called from invalid context at mm/slab.h:421 [ 395.979896] in_atomic(): 1, irqs_disabled(): 0, pid: 16254, name: openssl [ 395.996564] 2 locks held by openssl/16254: [ 396.010492] #0: 00000000347acb52 (sk_lock-AF_INET){+.+.}, at: do_tcp_setsockopt.isra.44+0x13b/0x9a0 [ 396.029838] GrapheneOS#1: 000000006c9552b5 (device_spinlock){+...}, at: tls_init+0x1d/0x280 [ 396.047675] CPU: 5 PID: 16254 Comm: openssl Tainted: G O 4.20.0-rc6+ GrapheneOS#25 [ 396.066019] Hardware name: Supermicro X10SRA-F/X10SRA-F, BIOS 2.0c 09/25/2017 [ 396.083537] Call Trace: [ 396.096265] dump_stack+0x5e/0x8b [ 396.109876] ___might_sleep+0x216/0x250 [ 396.123940] kmem_cache_alloc_trace+0x1b0/0x240 [ 396.138800] create_ctx+0x1f/0x60 [ 396.152504] tls_init+0xbd/0x280 [ 396.166135] tcp_set_ulp+0x191/0x2d0 [ 396.180035] ? tcp_set_ulp+0x2c/0x2d0 [ 396.193960] do_tcp_setsockopt.isra.44+0x148/0x9a0 [ 396.209013] __sys_setsockopt+0x7c/0xe0 [ 396.223054] __x64_sys_setsockopt+0x20/0x30 [ 396.237378] do_syscall_64+0x4a/0x180 [ 396.251200] entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: df9d4a1 ("net/tls: sleeping function from invalid context") Signed-off-by: Ganesh Goudar <[email protected]> Signed-off-by: David S. Miller <[email protected]>

[ Upstream commit c6ec179 ] create_ctx can be called from atomic context, hence use GFP_ATOMIC instead of GFP_KERNEL. [ 395.962599] BUG: sleeping function called from invalid context at mm/slab.h:421 [ 395.979896] in_atomic(): 1, irqs_disabled(): 0, pid: 16254, name: openssl [ 395.996564] 2 locks held by openssl/16254: [ 396.010492] #0: 00000000347acb52 (sk_lock-AF_INET){+.+.}, at: do_tcp_setsockopt.isra.44+0x13b/0x9a0 [ 396.029838] #1: 000000006c9552b5 (device_spinlock){+...}, at: tls_init+0x1d/0x280 [ 396.047675] CPU: 5 PID: 16254 Comm: openssl Tainted: G O 4.20.0-rc6+ #25 [ 396.066019] Hardware name: Supermicro X10SRA-F/X10SRA-F, BIOS 2.0c 09/25/2017 [ 396.083537] Call Trace: [ 396.096265] dump_stack+0x5e/0x8b [ 396.109876] ___might_sleep+0x216/0x250 [ 396.123940] kmem_cache_alloc_trace+0x1b0/0x240 [ 396.138800] create_ctx+0x1f/0x60 [ 396.152504] tls_init+0xbd/0x280 [ 396.166135] tcp_set_ulp+0x191/0x2d0 [ 396.180035] ? tcp_set_ulp+0x2c/0x2d0 [ 396.193960] do_tcp_setsockopt.isra.44+0x148/0x9a0 [ 396.209013] __sys_setsockopt+0x7c/0xe0 [ 396.223054] __x64_sys_setsockopt+0x20/0x30 [ 396.237378] do_syscall_64+0x4a/0x180 [ 396.251200] entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: df9d4a1 ("net/tls: sleeping function from invalid context") Signed-off-by: Ganesh Goudar <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…nal arrives while handle_mm_fault do_page_fault() forgot to relinquish mmap_sem if a signal came while handling handle_mm_fault() - due to say a ctl+c or oom etc. This would later cause a deadlock by acquiring it twice. This came to light when running libc testsuite tst-tls3-malloc test but is likely also the cause for prior seen LTP failures. Using lockdep clearly showed what the issue was. | # while true; do ./tst-tls3-malloc ; done | Didn't expect signal from child: got `Segmentation fault' | ^C | ============================================ | WARNING: possible recursive locking detected | 4.17.0+ GrapheneOS#25 Not tainted | -------------------------------------------- | tst-tls3-malloc/510 is trying to acquire lock: | 606c7728 (&mm->mmap_sem){++++}, at: __might_fault+0x28/0x5c | |but task is already holding lock: |606c7728 (&mm->mmap_sem){++++}, at: do_page_fault+0x9c/0x2a0 | | other info that might help us debug this: | Possible unsafe locking scenario: | | CPU0 | ---- | lock(&mm->mmap_sem); | lock(&mm->mmap_sem); | | *** DEADLOCK *** | ------------------------------------------------------------ What the change does is not obvious (note to myself) prior code was | do_page_fault | | down_read() <-- lock taken | handle_mm_fault <-- signal pending as this runs | if fatal_signal_pending | if VM_FAULT_ERROR | up_read | if user_mode | return <-- lock still held, this was the BUG New code | do_page_fault | | down_read() <-- lock taken | handle_mm_fault <-- signal pending as this runs | if fatal_signal_pending | if VM_FAULT_RETRY | return <-- not same case as above, but still OK since | core mm already relinq lock for FAULT_RETRY | ... | | < Now falls through for bug case above > | | up_read() <-- lock relinquished Cc: [email protected] Signed-off-by: Vineet Gupta <[email protected]>

Eric Biggers reported: > The following commit, which went into v4.20, introduced undefined behavior when > sys_rt_sigqueueinfo() is called with sig=0: > > commit 4ce5f9c > Author: Eric W. Biederman <[email protected]> > Date: Tue Sep 25 12:59:31 2018 +0200 > > signal: Use a smaller struct siginfo in the kernel > > In sig_specific_sicodes(), used from known_siginfo_layout(), the expression > '1ULL << ((sig)-1)' is undefined as it evaluates to 1ULL << 4294967295. > > Reproducer: > > #include <signal.h> > #include <sys/syscall.h> > #include <unistd.h> > > int main(void) > { > siginfo_t si = { .si_code = 1 }; > syscall(__NR_rt_sigqueueinfo, 0, 0, &si); > } > > UBSAN report for v5.0-rc1: > > UBSAN: Undefined behaviour in kernel/signal.c:2946:7 > shift exponent 4294967295 is too large for 64-bit type 'long unsigned int' > CPU: 2 PID: 346 Comm: syz_signal Not tainted 5.0.0-rc1 GrapheneOS#25 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x70/0xa5 lib/dump_stack.c:113 > ubsan_epilogue+0xd/0x40 lib/ubsan.c:159 > __ubsan_handle_shift_out_of_bounds+0x12c/0x170 lib/ubsan.c:425 > known_siginfo_layout+0xae/0xe0 kernel/signal.c:2946 > post_copy_siginfo_from_user kernel/signal.c:3009 [inline] > __copy_siginfo_from_user+0x35/0x60 kernel/signal.c:3035 > __do_sys_rt_sigqueueinfo kernel/signal.c:3553 [inline] > __se_sys_rt_sigqueueinfo kernel/signal.c:3549 [inline] > __x64_sys_rt_sigqueueinfo+0x31/0x70 kernel/signal.c:3549 > do_syscall_64+0x4c/0x1b0 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x433639 > Code: c4 18 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 27 00 00 c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fffcb289fc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000081 > RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000433639 > RDX: 00007fffcb289fd0 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: 00000000006b2018 R08: 000000000000004d R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401560 > R13: 00000000004015f0 R14: 0000000000000000 R15: 0000000000000000 I have looked at the other callers of siginmask and they all appear to in locations where sig can not be zero. I have looked at the code generation of adding an extra test against zero and gcc was able with a simple decrement instruction to combine the two tests together. So the at most adding this test cost a single cpu cycle. In practice that decrement instruction was already present as part of the mask comparison, so the only change was when the instruction was executed. So given that it is cheap, and obviously correct to update siginmask to verify the signal is not zero. Fix this issue there to avoid any future problems. Reported-by: Eric Biggers <[email protected]> Fixes: 4ce5f9c ("signal: Use a smaller struct siginfo in the kernel") Signed-off-by: "Eric W. Biederman" <[email protected]>

[ Upstream commit ee17e5d ] Eric Biggers reported: > The following commit, which went into v4.20, introduced undefined behavior when > sys_rt_sigqueueinfo() is called with sig=0: > > commit 4ce5f9c > Author: Eric W. Biederman <[email protected]> > Date: Tue Sep 25 12:59:31 2018 +0200 > > signal: Use a smaller struct siginfo in the kernel > > In sig_specific_sicodes(), used from known_siginfo_layout(), the expression > '1ULL << ((sig)-1)' is undefined as it evaluates to 1ULL << 4294967295. > > Reproducer: > > #include <signal.h> > #include <sys/syscall.h> > #include <unistd.h> > > int main(void) > { > siginfo_t si = { .si_code = 1 }; > syscall(__NR_rt_sigqueueinfo, 0, 0, &si); > } > > UBSAN report for v5.0-rc1: > > UBSAN: Undefined behaviour in kernel/signal.c:2946:7 > shift exponent 4294967295 is too large for 64-bit type 'long unsigned int' > CPU: 2 PID: 346 Comm: syz_signal Not tainted 5.0.0-rc1 #25 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x70/0xa5 lib/dump_stack.c:113 > ubsan_epilogue+0xd/0x40 lib/ubsan.c:159 > __ubsan_handle_shift_out_of_bounds+0x12c/0x170 lib/ubsan.c:425 > known_siginfo_layout+0xae/0xe0 kernel/signal.c:2946 > post_copy_siginfo_from_user kernel/signal.c:3009 [inline] > __copy_siginfo_from_user+0x35/0x60 kernel/signal.c:3035 > __do_sys_rt_sigqueueinfo kernel/signal.c:3553 [inline] > __se_sys_rt_sigqueueinfo kernel/signal.c:3549 [inline] > __x64_sys_rt_sigqueueinfo+0x31/0x70 kernel/signal.c:3549 > do_syscall_64+0x4c/0x1b0 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x433639 > Code: c4 18 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 27 00 00 c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fffcb289fc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000081 > RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000433639 > RDX: 00007fffcb289fd0 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: 00000000006b2018 R08: 000000000000004d R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401560 > R13: 00000000004015f0 R14: 0000000000000000 R15: 0000000000000000 I have looked at the other callers of siginmask and they all appear to in locations where sig can not be zero. I have looked at the code generation of adding an extra test against zero and gcc was able with a simple decrement instruction to combine the two tests together. So the at most adding this test cost a single cpu cycle. In practice that decrement instruction was already present as part of the mask comparison, so the only change was when the instruction was executed. So given that it is cheap, and obviously correct to update siginmask to verify the signal is not zero. Fix this issue there to avoid any future problems. Reported-by: Eric Biggers <[email protected]> Fixes: 4ce5f9c ("signal: Use a smaller struct siginfo in the kernel") Signed-off-by: "Eric W. Biederman" <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit d454854 upstream. KASAN report this: BUG: unable to handle kernel paging request at ffffffffa0097000 PGD 3870067 P4D 3870067 PUD 3871063 PMD 2326e2067 PTE 0 Oops: 0000 [#1 CPU: 0 PID: 5340 Comm: modprobe Not tainted 5.1.0-rc7+ #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 RIP: 0010:__list_add_valid+0x10/0x70 Code: c3 48 8b 06 55 48 89 e5 5d 48 39 07 0f 94 c0 0f b6 c0 c3 90 90 90 90 90 90 90 55 48 89 d0 48 8b 52 08 48 89 e5 48 39 f2 75 19 <48> 8b 32 48 39 f0 75 3a RSP: 0018:ffffc90000e23c68 EFLAGS: 00010246 RAX: ffffffffa00ad000 RBX: ffffffffa009d000 RCX: 0000000000000000 RDX: ffffffffa0097000 RSI: ffffffffa0097000 RDI: ffffffffa009d000 RBP: ffffc90000e23c68 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa0097000 R13: ffff888231797180 R14: 0000000000000000 R15: ffffc90000e23e78 FS: 00007fb215285540(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffa0097000 CR3: 000000022f144000 CR4: 00000000000006f0 Call Trace: v9fs_register_trans+0x2f/0x60 [9pnet ? 0xffffffffa0087000 p9_virtio_init+0x25/0x1000 [9pnet_virtio do_one_initcall+0x6c/0x3cc ? kmem_cache_alloc_trace+0x248/0x3b0 do_init_module+0x5b/0x1f1 load_module+0x1db1/0x2690 ? m_show+0x1d0/0x1d0 __do_sys_finit_module+0xc5/0xd0 __x64_sys_finit_module+0x15/0x20 do_syscall_64+0x6b/0x1d0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fb214d8e839 Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 RSP: 002b:00007ffc96554278 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 000055e67eed2aa0 RCX: 00007fb214d8e839 RDX: 0000000000000000 RSI: 000055e67ce95c2e RDI: 0000000000000003 RBP: 000055e67ce95c2e R08: 0000000000000000 R09: 000055e67eed2aa0 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 000055e67eeda500 R14: 0000000000040000 R15: 000055e67eed2aa0 Modules linked in: 9pnet_virtio(+) 9pnet gre rfkill vmw_vsock_virtio_transport_common vsock [last unloaded: 9pnet_virtio CR2: ffffffffa0097000 ---[ end trace 4a52bb13ff07b761 If register_virtio_driver() fails in p9_virtio_init, we should call v9fs_unregister_trans() to do cleanup. Link: http://lkml.kernel.org/r/[email protected] Cc: [email protected] Reported-by: Hulk Robot <[email protected]> Fixes: b530cc7 ("9p: add virtio transport") Signed-off-by: YueHaibing <[email protected]> Signed-off-by: Dominique Martinet <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…s while handle_mm_fault [ Upstream commit 4d44745 ] do_page_fault() forgot to relinquish mmap_sem if a signal came while handling handle_mm_fault() - due to say a ctl+c or oom etc. This would later cause a deadlock by acquiring it twice. This came to light when running libc testsuite tst-tls3-malloc test but is likely also the cause for prior seen LTP failures. Using lockdep clearly showed what the issue was. | # while true; do ./tst-tls3-malloc ; done | Didn't expect signal from child: got `Segmentation fault' | ^C | ============================================ | WARNING: possible recursive locking detected | 4.17.0+ #25 Not tainted | -------------------------------------------- | tst-tls3-malloc/510 is trying to acquire lock: | 606c7728 (&mm->mmap_sem){++++}, at: __might_fault+0x28/0x5c | |but task is already holding lock: |606c7728 (&mm->mmap_sem){++++}, at: do_page_fault+0x9c/0x2a0 | | other info that might help us debug this: | Possible unsafe locking scenario: | | CPU0 | ---- | lock(&mm->mmap_sem); | lock(&mm->mmap_sem); | | *** DEADLOCK *** | ------------------------------------------------------------ What the change does is not obvious (note to myself) prior code was | do_page_fault | | down_read() <-- lock taken | handle_mm_fault <-- signal pending as this runs | if fatal_signal_pending | if VM_FAULT_ERROR | up_read | if user_mode | return <-- lock still held, this was the BUG New code | do_page_fault | | down_read() <-- lock taken | handle_mm_fault <-- signal pending as this runs | if fatal_signal_pending | if VM_FAULT_RETRY | return <-- not same case as above, but still OK since | core mm already relinq lock for FAULT_RETRY | ... | | < Now falls through for bug case above > | | up_read() <-- lock relinquished Cc: [email protected] Signed-off-by: Vineet Gupta <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit 46e4a26 ] syzbot reports an error on flush_request_modules() for the second device. This workqueue was never initialised so simply remove the offending line. usb 1-1: USB disconnect, device number 2 em28xx 1-1:1.153: Disconnecting em28xx #1 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 12 at kernel/workqueue.c:3031 __flush_work.cold+0x2c/0x36 kernel/workqueue.c:3031 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.3.0-rc2+ #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xca/0x13e lib/dump_stack.c:113 panic+0x2a3/0x6da kernel/panic.c:219 __warn.cold+0x20/0x4a kernel/panic.c:576 report_bug+0x262/0x2a0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1026 RIP: 0010:__flush_work.cold+0x2c/0x36 kernel/workqueue.c:3031 Code: 9a 22 00 48 c7 c7 20 e4 c5 85 e8 d9 3a 0d 00 0f 0b 45 31 e4 e9 98 86 ff ff e8 51 9a 22 00 48 c7 c7 20 e4 c5 85 e8 be 3a 0d 00 <0f> 0b 45 31 e4 e9 7d 86 ff ff e8 36 9a 22 00 48 c7 c7 20 e4 c5 85 RSP: 0018:ffff8881da20f720 EFLAGS: 00010286 RAX: 0000000000000024 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8128a0fd RDI: ffffed103b441ed6 RBP: ffff8881da20f888 R08: 0000000000000024 R09: fffffbfff11acd9a R10: fffffbfff11acd99 R11: ffffffff88d66ccf R12: 0000000000000000 R13: 0000000000000001 R14: ffff8881c6685df8 R15: ffff8881d2a85b78 flush_request_modules drivers/media/usb/em28xx/em28xx-cards.c:3325 [inline] em28xx_usb_disconnect.cold+0x280/0x2a6 drivers/media/usb/em28xx/em28xx-cards.c:4023 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1120 [inline] device_release_driver_internal+0x404/0x4c0 drivers/base/dd.c:1151 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:556 device_del+0x420/0xb10 drivers/base/core.c:2288 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199 hub_port_connect drivers/usb/core/hub.c:4949 [inline] hub_port_connect_change drivers/usb/core/hub.c:5213 [inline] port_event drivers/usb/core/hub.c:5359 [inline] hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 process_scheduled_works kernel/workqueue.c:2331 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: be7fd3c ("media: em28xx: Hauppauge DualHD second tuner functionality) Reviewed-by: Ezequiel Garcia <[email protected]> Reviewed-by: Brad Love <[email protected]> Reported-by: [email protected] Signed-off-by: Sean Young <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

The RCU lock is insufficient to protect the radix tree iteration as a deletion from the tree can occur before we take the spinlock to tag the entry. In 4.19, this has manifested as a bug with the following trace: kernel BUG at lib/radix-tree.c:1429! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 7 PID: 6935 Comm: syz-executor.2 Not tainted 4.19.36 #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 RIP: 0010:radix_tree_tag_set+0x200/0x2f0 lib/radix-tree.c:1429 Code: 00 00 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 89 44 24 10 e8 a3 29 7e fe 48 8b 44 24 10 48 0f ab 03 e9 d2 fe ff ff e8 90 29 7e fe <0f> 0b 48 c7 c7 e0 5a 87 84 e8 f0 e7 08 ff 4c 89 ef e8 4a ff ac fe RSP: 0018:ffff88837b13fb60 EFLAGS: 00010016 RAX: 0000000000040000 RBX: ffff8883c5515d58 RCX: ffffffff82cb2ef0 RDX: 0000000000000b72 RSI: ffffc90004cf2000 RDI: ffff8883c5515d98 RBP: ffff88837b13fb98 R08: ffffed106f627f7e R09: ffffed106f627f7e R10: 0000000000000001 R11: ffffed106f627f7d R12: 0000000000000004 R13: ffffea000d7fea80 R14: 1ffff1106f627f6f R15: 0000000000000002 FS: 00007fa1b8df2700(0000) GS:ffff8883e2fc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa1b8df1db8 CR3: 000000037d4d2001 CR4: 0000000000160ee0 Call Trace: memfd_tag_pins mm/memfd.c:51 [inline] memfd_wait_for_pins+0x2c5/0x12d0 mm/memfd.c:81 memfd_add_seals mm/memfd.c:215 [inline] memfd_fcntl+0x33d/0x4a0 mm/memfd.c:247 do_fcntl+0x589/0xeb0 fs/fcntl.c:421 __do_sys_fcntl fs/fcntl.c:463 [inline] __se_sys_fcntl fs/fcntl.c:448 [inline] __x64_sys_fcntl+0x12d/0x180 fs/fcntl.c:448 do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:293 The problem does not occur in mainline due to the XArray rewrite which changed the locking to exclude modification of the tree during iteration. At the time, nobody realised this was a bugfix. Backport the locking changes to stable. Cc: [email protected] Reported-by: zhong jiang <[email protected]> Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

In a case when a ptp chardev (like /dev/ptp0) is open but an underlying device is removed, closing this file leads to a race. This reproduces easily in a kvm virtual machine: ts# cat openptp0.c int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); } ts# uname -r 5.5.0-rc3-46cf053e ts# cat /proc/cmdline ... slub_debug=FZP ts# modprobe ptp_kvm ts# ./openptp0 & [1] 670 opened /dev/ptp0, sleeping 10s... ts# rmmod ptp_kvm ts# ls /dev/ptp* ls: cannot access '/dev/ptp*': No such file or directory ts# ...woken up [ 48.010809] general protection fault: 0000 [#1] SMP [ 48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25 [ 48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ... [ 48.016270] RIP: 0010:module_put.part.0+0x7/0x80 [ 48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202 [ 48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0 [ 48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b [ 48.019470] ... ^^^ a slub poison [ 48.023854] Call Trace: [ 48.024050] __fput+0x21f/0x240 [ 48.024288] task_work_run+0x79/0x90 [ 48.024555] do_exit+0x2af/0xab0 [ 48.024799] ? vfs_write+0x16a/0x190 [ 48.025082] do_group_exit+0x35/0x90 [ 48.025387] __x64_sys_exit_group+0xf/0x10 [ 48.025737] do_syscall_64+0x3d/0x130 [ 48.026056] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.026479] RIP: 0033:0x7f53b12082f6 [ 48.026792] ... [ 48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm] [ 48.045001] Fixing recursive fault but reboot is needed! This happens in: static void __fput(struct file *file) { ... if (file->f_op->release) file->f_op->release(inode, file); <<< cdev is kfree'd here if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL && !(mode & FMODE_PATH))) { cdev_put(inode->i_cdev); <<< cdev fields are accessed here Namely: __fput() posix_clock_release() kref_put(&clk->kref, delete_clock) <<< the last reference delete_clock() delete_ptp_clock() kfree(ptp) <<< cdev is embedded in ptp cdev_put module_put(p->owner) <<< *p is kfree'd, bang! Here cdev is embedded in posix_clock which is embedded in ptp_clock. The race happens because ptp_clock's lifetime is controlled by two refcounts: kref and cdev.kobj in posix_clock. This is wrong. Make ptp_clock's sysfs device a parent of cdev with cdev_device_add() created especially for such cases. This way the parent device with its ptp_clock is not released until all references to the cdev are released. This adds a requirement that an initialized but not exposed struct device should be provided to posix_clock_register() by a caller instead of a simple dev_t. This approach was adopted from the commit 72139df ("watchdog: Fix the race between the release of watchdog_core_data and cdev"). See details of the implementation in the commit 233ed09 ("chardev: add helper function to register char devs with a struct device"). Link: https://lore.kernel.org/linux-fsdevel/[email protected]/T/#u Analyzed-by: Stephen Johnston <[email protected]> Analyzed-by: Vern Lovejoy <[email protected]> Signed-off-by: Vladis Dronov <[email protected]> Acked-by: Richard Cochran <[email protected]> Signed-off-by: David S. Miller <[email protected]>

[ Upstream commit a33121e ] In a case when a ptp chardev (like /dev/ptp0) is open but an underlying device is removed, closing this file leads to a race. This reproduces easily in a kvm virtual machine: ts# cat openptp0.c int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); } ts# uname -r 5.5.0-rc3-46cf053e ts# cat /proc/cmdline ... slub_debug=FZP ts# modprobe ptp_kvm ts# ./openptp0 & [1] 670 opened /dev/ptp0, sleeping 10s... ts# rmmod ptp_kvm ts# ls /dev/ptp* ls: cannot access '/dev/ptp*': No such file or directory ts# ...woken up [ 48.010809] general protection fault: 0000 [#1] SMP [ 48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25 [ 48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ... [ 48.016270] RIP: 0010:module_put.part.0+0x7/0x80 [ 48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202 [ 48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0 [ 48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b [ 48.019470] ... ^^^ a slub poison [ 48.023854] Call Trace: [ 48.024050] __fput+0x21f/0x240 [ 48.024288] task_work_run+0x79/0x90 [ 48.024555] do_exit+0x2af/0xab0 [ 48.024799] ? vfs_write+0x16a/0x190 [ 48.025082] do_group_exit+0x35/0x90 [ 48.025387] __x64_sys_exit_group+0xf/0x10 [ 48.025737] do_syscall_64+0x3d/0x130 [ 48.026056] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.026479] RIP: 0033:0x7f53b12082f6 [ 48.026792] ... [ 48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm] [ 48.045001] Fixing recursive fault but reboot is needed! This happens in: static void __fput(struct file *file) { ... if (file->f_op->release) file->f_op->release(inode, file); <<< cdev is kfree'd here if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL && !(mode & FMODE_PATH))) { cdev_put(inode->i_cdev); <<< cdev fields are accessed here Namely: __fput() posix_clock_release() kref_put(&clk->kref, delete_clock) <<< the last reference delete_clock() delete_ptp_clock() kfree(ptp) <<< cdev is embedded in ptp cdev_put module_put(p->owner) <<< *p is kfree'd, bang! Here cdev is embedded in posix_clock which is embedded in ptp_clock. The race happens because ptp_clock's lifetime is controlled by two refcounts: kref and cdev.kobj in posix_clock. This is wrong. Make ptp_clock's sysfs device a parent of cdev with cdev_device_add() created especially for such cases. This way the parent device with its ptp_clock is not released until all references to the cdev are released. This adds a requirement that an initialized but not exposed struct device should be provided to posix_clock_register() by a caller instead of a simple dev_t. This approach was adopted from the commit 72139df ("watchdog: Fix the race between the release of watchdog_core_data and cdev"). See details of the implementation in the commit 233ed09 ("chardev: add helper function to register char devs with a struct device"). Link: https://lore.kernel.org/linux-fsdevel/[email protected]/T/#u Analyzed-by: Stephen Johnston <[email protected]> Analyzed-by: Vern Lovejoy <[email protected]> Signed-off-by: Vladis Dronov <[email protected]> Acked-by: Richard Cochran <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

thestinger added type-enhancement port-grsecurity labels May 15, 2017

thestinger changed the title ~~device timing side channels~~ mitigate device timing side channels May 15, 2017

thestinger self-assigned this May 16, 2017

thestinger closed this as completed May 16, 2017

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mitigate device timing side channels #25

mitigate device timing side channels #25

thestinger commented May 15, 2017

thestinger commented May 16, 2017

mitigate device timing side channels #25

mitigate device timing side channels #25

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thestinger commented May 15, 2017

thestinger commented May 16, 2017