Avoid use of PATH_MAX (Debian bug #1009066) #98
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
PATH_MAX is undefined on GNU Hurd (as is allowed by POSIX), and is in some regards problematic anyway (cf https://www.gnu.org/software/hurd/hurd/porting/guidelines.html#PATH_MAX_tt_MAX_PATH_tt_MAXPATHL ). This patch from Yavor Doganov instead dynamically allocates `*resolvedpath` as necessary using `realpath(childpath, NULL)` (and then makes sure to free it later). Signed-off-by: Matthew Vernon <[email protected]>
carenas
suggested changes
Apr 11, 2022
| BOOL isSame; | ||
| size_t rlen; | ||
| if (realpath(childpath, resolvedpath) == NULL) | ||
| if ((resolvedpath = realpath(childpath, NULL)) == NULL) |
There was a problem hiding this comment.
realpath(path, NULL) is only valid in POSIX.1-2008, so we would need to check for that and enable this code conditionally based on that.
IMHO, since only Hurd doesn't have PATH_MAX even when it provides realpath(), the current code is more portable, and was indeed fixed so it will be just ignored in Hurd since adf76fa
There was a problem hiding this comment.
Hi,
Thanks, yes the right answer is to cherry-pick adf76fa on top of my Debian tree; so I'll do that and close this.
Thanks for the pointer :)
| { | ||
| BOOL contained; | ||
| resolvedpath = (char *)realloc(resolvedpath, rlen + 1); |
There was a problem hiding this comment.
this could fail and in that case the original resolvedpath might leak, and more importantly will crash next
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
PATH_MAX is undefined on GNU Hurd (as is allowed by POSIX), and is in
some regards problematic anyway (cf
https://www.gnu.org/software/hurd/hurd/porting/guidelines.html#PATH_MAX_tt_MAX_PATH_tt_MAXPATHL
).
This patch from Yavor Doganov instead dynamically allocates
*resolvedpathas necessary usingrealpath(childpath, NULL)(andthen makes sure to free it later).
Signed-off-by: Matthew Vernon [email protected]