6.1-stable review patch. If anyone has any objections, please let me know.
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From: Mickaël Salaün mic@digikod.net
[ Upstream commit 49440290a0935f428a1e43a5ac8dc275a647ff80 ]
A corrupted filesystem (e.g. bcachefs) might return weird files. Instead of throwing a warning and allowing access to such file, treat them as regular files.
Cc: Dave Chinner david@fromorbit.com Cc: Kent Overstreet kent.overstreet@linux.dev Cc: Paul Moore paul@paul-moore.com Reported-by: syzbot+34b68f850391452207df@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/000000000000a65b35061cffca61@google.com Reported-by: syzbot+360866a59e3c80510a62@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/67379b3f.050a0220.85a0.0001.GAE@google.com Reported-by: Ubisectech Sirius bugreport@ubisectech.com Closes: https://lore.kernel.org/r/c426821d-8380-46c4-a494-7008bbd7dd13.bugreport@ubi... Fixes: cb2c7d1a1776 ("landlock: Support filesystem access-control") Reviewed-by: Günther Noack gnoack3000@gmail.com Link: https://lore.kernel.org/r/20250110153918.241810-1-mic@digikod.net Signed-off-by: Mickaël Salaün mic@digikod.net Signed-off-by: Sasha Levin sashal@kernel.org --- security/landlock/fs.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/security/landlock/fs.c b/security/landlock/fs.c index 7b0e5976113c2..7b95afcc6b437 100644 --- a/security/landlock/fs.c +++ b/security/landlock/fs.c @@ -669,10 +669,6 @@ static inline access_mask_t get_mode_access(const umode_t mode) switch (mode & S_IFMT) { case S_IFLNK: return LANDLOCK_ACCESS_FS_MAKE_SYM; - case 0: - /* A zero mode translates to S_IFREG. */ - case S_IFREG: - return LANDLOCK_ACCESS_FS_MAKE_REG; case S_IFDIR: return LANDLOCK_ACCESS_FS_MAKE_DIR; case S_IFCHR: @@ -683,9 +679,12 @@ static inline access_mask_t get_mode_access(const umode_t mode) return LANDLOCK_ACCESS_FS_MAKE_FIFO; case S_IFSOCK: return LANDLOCK_ACCESS_FS_MAKE_SOCK; + case S_IFREG: + case 0: + /* A zero mode translates to S_IFREG. */ default: - WARN_ON_ONCE(1); - return 0; + /* Treats weird files as regular files. */ + return LANDLOCK_ACCESS_FS_MAKE_REG; } }