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| author | Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> | 2022-04-13 14:42:51 +0300 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2022-04-13 20:00:49 +0300 |
| commit | 64c4a37ac04eeb43c42d272f6e6c8c12bfcf4304 (patch) | |
| tree | ee678309f2a4a7c47664fc0a436d5d6968046c65 /fs/cifs | |
| parent | 1ddff774164f1bcd0fcf988f7a5bb24270fbdf2c (diff) | |
| download | linux-64c4a37ac04eeb43c42d272f6e6c8c12bfcf4304.tar.xz | |
cifs: potential buffer overflow in handling symlinks
Smatch printed a warning:
arch/x86/crypto/poly1305_glue.c:198 poly1305_update_arch() error:
__memcpy() 'dctx->buf' too small (16 vs u32max)
It's caused because Smatch marks 'link_len' as untrusted since it comes
from sscanf(). Add a check to ensure that 'link_len' is not larger than
the size of the 'link_str' buffer.
Fixes: c69c1b6eaea1 ("cifs: implement CIFSParseMFSymlink()")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs')
| -rw-r--r-- | fs/cifs/link.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 852e54ee82c2..bbdf3281559c 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -85,6 +85,9 @@ parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len, if (rc != 1) return -EINVAL; + if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN) + return -EINVAL; + rc = symlink_hash(link_len, link_str, md5_hash); if (rc) { cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc); |