Avoid use of PATH_MAX (Debian bug #1009066) #98
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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 <matthew@debian.org>
carenas
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Apr 11, 2022
| BOOL isSame; | ||
| size_t rlen; | ||
| if (realpath(childpath, resolvedpath) == NULL) | ||
| if ((resolvedpath = realpath(childpath, NULL)) == NULL) |
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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
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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); |
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this could fail and in that case the original resolvedpath might leak, and more importantly will crash next
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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 matthew@debian.org