fix reported defect from coverity scan #1706
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| @@ -862,7 +862,7 @@ void setup_log(struct io_log **log, struct log_params *p, | |||
| l->log_ddir_mask = LOG_OFFSET_SAMPLE_BIT; | |||
| if (l->log_prio) | |||
| l->log_ddir_mask |= LOG_PRIO_SAMPLE_BIT; | |||
| if (l->td->o.log_max == IO_LOG_SAMPLE_BOTH) | |||
| if (l->td && l->td->o.log_max == IO_LOG_SAMPLE_BOTH) | |||
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This is a work-around just to appease the checker, not a huge fan. Either p->td is always valid, and in which case l->td is also always valid, or it's valid to call setup_log() with NULL p->td and checking is needed. Decide which one it is and do the fix based on that.
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Yes setup_log() gets called with NULL p->td for agg-read_bw.log, agg-write_bw.log and agg-trim_bw.log. So this check is required.
I think this is the reason we have the same check few lines above.
if (l->td && l->td->o.io_submit_mode != IO_MODE_OFFLOAD)
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Gotcha - then the fix looks fine to me. Can you add a comment as to when it's NULL?
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Done, please take a look.
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Ah my mistake, I only updated the commit message previously. Its should be done now.
ankit-sam
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Fix the two Null pointer dereferences issue reported by Coverity scan Null pointer dereferences (FORWARD_NULL) Dereferencing null pointer "l->td" Null pointer dereferences (REVERSE_INULL) Null-checking "p->td" suggests that it may be null, but it has already been dereferenced on all paths leading to the check. For aggregate read, write and trim bandwidth log, the setup_log function gets called with NULL pointer reference for thread data. Thus before dereferencing further we should check "l->td". Signed-off-by: Ankit Kumar <[email protected]>
Fix the two Null pointer dereferences issue reported by Coverity scan
Null pointer dereferences (FORWARD_NULL)
Dereferencing null pointer "l->td"
Null pointer dereferences (REVERSE_INULL)
Null-checking "p->td" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.