d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

etc/systemd/zfs-mount-generator: avoid strndupa

Browse Source 
The non-standard strndupa function is not implemented by musl libc,
and can be dangerous due to its potential to blow the stack.  (musl
_does_ implement strdupa, used elsewhere in this function.)

With a similar amount of code, we can use a heap allocation to
construct the pool name, which is musl-friendly and doesn't have
potential stack problems.

(Why care about musl when systemd only supports glibc?  Some distros
patch systemd with portability fixes, and it would be nice to be able
to use ZFS on those distros.)

 Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alyssa Ross <alyssa.ross@unikie.com>
Closes #14327
This commit is contained in:
Alyssa Ross 2023-01-10 21:40:31 +00:00 committed by GitHub
parent fc45975ec8
commit 1f19826c9a
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
etc/systemd/system-generators/zfs-mount-generator.c
View File

@ -224,9 +224,10 @@ line_worker(char *line, const char *cachefile)
const char *p_systemd_ignore = strtok_r(NULL, "\t", &toktmp) ?: "-";
/* END CSTYLED */
const char *pool = dataset;
if ((toktmp = strchr(pool, '/')) != NULL)
pool = strndupa(pool, toktmp - pool);
size_t pool_len = strlen(dataset);
if ((toktmp = strchr(dataset, '/')) != NULL)
pool_len = toktmp - dataset;
const char *pool = *(tofree++) = strndup(dataset, pool_len);
if (p_nbmand == NULL) {
fprintf(stderr, PROGNAME "[%d]: %s: not enough tokens!\n",
@ -734,7 +735,7 @@ line_worker(char *line, const char *cachefile)
if (tofree >= tofree_all + nitems(tofree_all)) {
/*
* This won't happen as-is:
* we've got 8 slots and allocate 4 things at most.
* we've got 8 slots and allocate 5 things at most.
*/
fprintf(stderr,
PROGNAME "[%d]: %s: need to free %zu > %zu!\n",