6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Guangshuo Li <redacted>
[ Upstream commit d40c24634fe077a0dc91fd11fccf44ce12b454d5 ]
check_lock_range() uses inclusive ranges. Its callers pass the end
offset as start + length - 1, so start == end represents a valid
single-byte range rather than an empty range.
The start == end shortcut therefore skips mandatory byte-range lock
checks for one-byte reads, writes, copychunk operations and one-byte
truncate ranges. A conflicting lock covering that byte is not checked
and the operation is allowed to proceed.
Remove the shortcut. The truncate size == inode->i_size case is already
handled by only calling check_lock_range() when the new size differs
from the current file size.
Fixes: 5d510ac31626 ("ksmbd: skip lock-range check on equal size to avoid size==0 underflow")
Signed-off-by: Guangshuo Li <redacted>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/smb/server/vfs.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c
index 1834dd4f255ec..2915f7e98fe93 100644
--- a/fs/smb/server/vfs.c
+++ b/fs/smb/server/vfs.c
@@ -330,9 +330,6 @@ static int check_lock_range(struct file *filp, loff_t start, loff_t end,
struct file_lock_context *ctx = file_inode(filp)->i_flctx;
int error = 0;
- if (start == end)
- return 0;
-
if (!ctx || list_empty_careful(&ctx->flc_posix))
return 0;
--
2.53.0