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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-10-21 21:57:38 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-17 17:09:55 +0300 |
| commit | f6046d0b8fc650461b837bae0a74154a4df7dc8e (patch) | |
| tree | e3cf81a640d6a8e61d7e410dd7de059cbbb5618a | |
| parent | 3dfb40da84f26dd35dd9bbaf626a2424565b8406 (diff) | |
| download | linux-f6046d0b8fc650461b837bae0a74154a4df7dc8e.tar.xz | |
9p: fix slab cache name creation for real
commit a360f311f57a36e96d88fa8086b749159714dcd2 upstream.
This was attempted by using the dev_name in the slab cache name, but as
Omar Sandoval pointed out, that can be an arbitrary string, eg something
like "/dev/root". Which in turn trips verify_dirent_name(), which fails
if a filename contains a slash.
So just make it use a sequence counter, and make it an atomic_t to avoid
any possible races or locking issues.
Reported-and-tested-by: Omar Sandoval <osandov@fb.com>
Link: https://lore.kernel.org/all/ZxafcO8KWMlXaeWE@telecaster.dhcp.thefacebook.com/
Fixes: 79efebae4afc ("9p: Avoid creating multiple slab caches with the same name")
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/9p/client.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/net/9p/client.c b/net/9p/client.c index 9e7b9151816d..09f8ced9f8bb 100644 --- a/net/9p/client.c +++ b/net/9p/client.c @@ -977,6 +977,7 @@ error: struct p9_client *p9_client_create(const char *dev_name, char *options) { int err; + static atomic_t seqno = ATOMIC_INIT(0); struct p9_client *clnt; char *client_id; char *cache_name; @@ -1036,7 +1037,8 @@ struct p9_client *p9_client_create(const char *dev_name, char *options) if (err) goto close_trans; - cache_name = kasprintf(GFP_KERNEL, "9p-fcall-cache-%s", dev_name); + cache_name = kasprintf(GFP_KERNEL, + "9p-fcall-cache-%u", atomic_inc_return(&seqno)); if (!cache_name) { err = -ENOMEM; goto close_trans; |