| Message ID | 22307ecd-3254-6077-8bc7-02693338b586@virtuozzo.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] keys: proc_keys_next should increase position index | expand |
Vasily Averin <vvs@virtuozzo.com> wrote: > If seq_file .next fuction does not change position index, "function" > <<<< and whole last lien again "line" I can fix these up for you. > https://bugzilla.kernel.org/show_bug.cgi?id=206283 I wonder if this should have a tag - it looks kind of out of place without one, but I can't find one suggested. David
On 1/31/20 8:19 PM, David Howells wrote: > Vasily Averin <vvs@virtuozzo.com> wrote: >> If seq_file .next fuction does not change position index, > "function" >> <<<< and whole last lien again > "line" > > I can fix these up for you. thank you! >> https://bugzilla.kernel.org/show_bug.cgi?id=206283 > > I wonder if this should have a tag - it looks kind of out of place without > one, but I can't find one suggested. Some maintainers of another subsystems asked me to add Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") however frankly speaking I do not think it is required in this case. Thank you, Vasily Averin
diff --git a/security/keys/proc.c b/security/keys/proc.c index 415f3f1..d0cde66 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -139,6 +139,8 @@ static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos) n = key_serial_next(p, v); if (n) *_pos = key_node_serial(n); + else + (*_pos)++; return n; }
If seq_file .next fuction does not change position index, read after some lseek can generate unexpected output: $ dd if=/proc/keys bs=1 # full usual output 0f6bfdf5 I--Q--- 2 perm 3f010000 1000 1000 user 4af2f79ab8848d0a: 740 1fb91b32 I--Q--- 3 perm 1f3f0000 1000 65534 keyring _uid.1000: 2 27589480 I--Q--- 1 perm 0b0b0000 0 0 user invocation_id: 16 2f33ab67 I--Q--- 152 perm 3f030000 0 0 keyring _ses: 2 33f1d8fa I--Q--- 4 perm 3f030000 1000 1000 keyring _ses: 1 3d427fda I--Q--- 2 perm 3f010000 1000 1000 user 69ec44aec7678e5a: 740 3ead4096 I--Q--- 1 perm 1f3f0000 1000 65534 keyring _uid_ses.1000: 1 521+0 records in 521+0 records out 521 bytes copied, 0,00123769 s, 421 kB/s $ dd if=/proc/keys bs=500 skip=1 # read after lseek in middle of last line dd: /proc/keys: cannot skip to specified offset g _uid_ses.1000: 1 <<<< end of last line 3ead4096 I--Q--- 1 perm 1f3f0000 1000 65534 keyring _uid_ses.1000: 1 <<<< and whole last lien again 0+1 records in 0+1 records out 97 bytes copied, 0,000135035 s, 718 kB/s $ dd if=/proc/keys bs=1000 skip=1 # read after lseek beyond end of file dd: /proc/keys: cannot skip to specified offset 3ead4096 I--Q--- 1 perm 1f3f0000 1000 65534 keyring _uid_ses.1000: 1 <<<< generates last line 0+1 records in 0+1 records out 76 bytes copied, 0,000119981 s, 633 kB/s Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin <vvs@virtuozzo.com> --- security/keys/proc.c | 2 ++ 1 file changed, 2 insertions(+)