| Message ID | 20220511185909.175110-2-tadeusz.struk@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2,1/2] exfat: move is_valid_cluster to a common header | expand |
> Syzbot reported slab-out-of-bounds read in exfat_clear_bitmap. > This was triggered by reproducer calling truncute with size 0, which > causes the following trace: > > BUG: KASAN: slab-out-of-bounds in exfat_clear_bitmap+0x147/0x490 > fs/exfat/balloc.c:174 Read of size 8 at addr ffff888115aa9508 by task syz- > executor251/365 > > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b > lib/dump_stack.c:118 > print_address_description+0x81/0x3c0 mm/kasan/report.c:233 > __kasan_report mm/kasan/report.c:419 [inline] > kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 > exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174 > exfat_free_cluster+0x25a/0x4a0 fs/exfat/fatent.c:181 > __exfat_truncate+0x99e/0xe00 fs/exfat/file.c:217 > exfat_truncate+0x11b/0x4f0 fs/exfat/file.c:243 > exfat_setattr+0xa03/0xd40 fs/exfat/file.c:339 > notify_change+0xb76/0xe10 fs/attr.c:336 > do_truncate+0x1ea/0x2d0 fs/open.c:65 > > Add checks to validate if cluster number is within valid range in > exfat_clear_bitmap() and exfat_set_bitmap() > > Cc: Namjae Jeon <linkinjeon@kernel.org> > Cc: Sungjong Seo <sj1557.seo@samsung.com> > Cc: linux-fsdevel@vger.kernel.org > Cc: stable@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > > Link: https://protect2.fireeye.com/v1/url?k=24a746d8-45dcec51-24a6cd97- > 74fe48600034-8e4653a49a463f3c&q=1&e=0efc824d-6463-4253-9cd7- > ce3199dbf513&u=https%3A%2F%2Fsyzkaller.appspot.com%2Fbug%3Fid%3D50381fc738 > 21ecae743b8cf24b4c9a04776f767c > Reported-by: syzbot+a4087e40b9c13aad7892@syzkaller.appspotmail.com > Fixes: 1e49a94cf707 ("exfat: add bitmap operations") > Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org> Looks good. And it seems that WARN_ON() is no longer needed. Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com> > --- > v2: > - Use is_valid_cluster() helper to validate clu > --- > fs/exfat/balloc.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c index > 03f142307174..92f5b5b5a0d0 100644 > --- a/fs/exfat/balloc.c > +++ b/fs/exfat/balloc.c > @@ -149,6 +149,9 @@ int exfat_set_bitmap(struct inode *inode, unsigned int > clu, bool sync) > struct exfat_sb_info *sbi = EXFAT_SB(sb); > > WARN_ON(clu < EXFAT_FIRST_CLUSTER); > + if (!is_valid_cluster(sbi, clu)) > + return -EINVAL; > + > ent_idx = CLUSTER_TO_BITMAP_ENT(clu); > i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx); > b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx); @@ -167,6 +170,9 @@ > void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync) > struct exfat_mount_options *opts = &sbi->options; > > WARN_ON(clu < EXFAT_FIRST_CLUSTER); > + if (!is_valid_cluster(sbi, clu)) > + return; > + > ent_idx = CLUSTER_TO_BITMAP_ENT(clu); > i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx); > b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx); > -- > 2.36.1
On 5/15/22 07:52, Sungjong Seo wrote: >> Syzbot reported slab-out-of-bounds read in exfat_clear_bitmap. >> This was triggered by reproducer calling truncute with size 0, which >> causes the following trace: >> >> BUG: KASAN: slab-out-of-bounds in exfat_clear_bitmap+0x147/0x490 >> fs/exfat/balloc.c:174 Read of size 8 at addr ffff888115aa9508 by task syz- >> executor251/365 >> >> Call Trace: >> __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b >> lib/dump_stack.c:118 >> print_address_description+0x81/0x3c0 mm/kasan/report.c:233 >> __kasan_report mm/kasan/report.c:419 [inline] >> kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 >> __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 >> exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174 >> exfat_free_cluster+0x25a/0x4a0 fs/exfat/fatent.c:181 >> __exfat_truncate+0x99e/0xe00 fs/exfat/file.c:217 >> exfat_truncate+0x11b/0x4f0 fs/exfat/file.c:243 >> exfat_setattr+0xa03/0xd40 fs/exfat/file.c:339 >> notify_change+0xb76/0xe10 fs/attr.c:336 >> do_truncate+0x1ea/0x2d0 fs/open.c:65 >> >> Add checks to validate if cluster number is within valid range in >> exfat_clear_bitmap() and exfat_set_bitmap() >> >> Cc: Namjae Jeon<linkinjeon@kernel.org> >> Cc: Sungjong Seo<sj1557.seo@samsung.com> >> Cc:linux-fsdevel@vger.kernel.org >> Cc:stable@vger.kernel.org >> Cc:linux-kernel@vger.kernel.org >> >> Link:https://protect2.fireeye.com/v1/url?k=24a746d8-45dcec51-24a6cd97- >> 74fe48600034-8e4653a49a463f3c&q=1&e=0efc824d-6463-4253-9cd7- >> ce3199dbf513&u=https%3A%2F%2Fsyzkaller.appspot.com%2Fbug%3Fid%3D50381fc738 >> 21ecae743b8cf24b4c9a04776f767c >> Reported-by:syzbot+a4087e40b9c13aad7892@syzkaller.appspotmail.com >> Fixes: 1e49a94cf707 ("exfat: add bitmap operations") >> Signed-off-by: Tadeusz Struk<tadeusz.struk@linaro.org> > Looks good. > And it seems that WARN_ON() is no longer needed. Right. Do you want me to send a follow up patch that drops the WARN_ONs? > Reviewed-by: Sungjong Seo<sj1557.seo@samsung.com> > Thank you.
2022-05-16 23:51 GMT+09:00, Tadeusz Struk <tadeusz.struk@linaro.org>: > On 5/15/22 07:52, Sungjong Seo wrote: >>> Syzbot reported slab-out-of-bounds read in exfat_clear_bitmap. >>> This was triggered by reproducer calling truncute with size 0, which >>> causes the following trace: >>> >>> BUG: KASAN: slab-out-of-bounds in exfat_clear_bitmap+0x147/0x490 >>> fs/exfat/balloc.c:174 Read of size 8 at addr ffff888115aa9508 by task >>> syz- >>> executor251/365 >>> >>> Call Trace: >>> __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b >>> lib/dump_stack.c:118 >>> print_address_description+0x81/0x3c0 mm/kasan/report.c:233 >>> __kasan_report mm/kasan/report.c:419 [inline] >>> kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 >>> __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 >>> exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174 >>> exfat_free_cluster+0x25a/0x4a0 fs/exfat/fatent.c:181 >>> __exfat_truncate+0x99e/0xe00 fs/exfat/file.c:217 >>> exfat_truncate+0x11b/0x4f0 fs/exfat/file.c:243 >>> exfat_setattr+0xa03/0xd40 fs/exfat/file.c:339 >>> notify_change+0xb76/0xe10 fs/attr.c:336 >>> do_truncate+0x1ea/0x2d0 fs/open.c:65 >>> >>> Add checks to validate if cluster number is within valid range in >>> exfat_clear_bitmap() and exfat_set_bitmap() >>> >>> Cc: Namjae Jeon<linkinjeon@kernel.org> >>> Cc: Sungjong Seo<sj1557.seo@samsung.com> >>> Cc:linux-fsdevel@vger.kernel.org >>> Cc:stable@vger.kernel.org >>> Cc:linux-kernel@vger.kernel.org >>> >>> Link:https://protect2.fireeye.com/v1/url?k=24a746d8-45dcec51-24a6cd97- >>> 74fe48600034-8e4653a49a463f3c&q=1&e=0efc824d-6463-4253-9cd7- >>> ce3199dbf513&u=https%3A%2F%2Fsyzkaller.appspot.com%2Fbug%3Fid%3D50381fc738 >>> 21ecae743b8cf24b4c9a04776f767c >>> Reported-by:syzbot+a4087e40b9c13aad7892@syzkaller.appspotmail.com >>> Fixes: 1e49a94cf707 ("exfat: add bitmap operations") >>> Signed-off-by: Tadeusz Struk<tadeusz.struk@linaro.org> >> Looks good. >> And it seems that WARN_ON() is no longer needed. > > Right. Do you want me to send a follow up patch that drops the WARN_ONs? You don't need to do it. I have applied this patch to #exfat dev branch after removing it. Note that I have combined 1/2 into 2/2 patch. Thanks! > >> Reviewed-by: Sungjong Seo<sj1557.seo@samsung.com> >> > > Thank you. > > -- > Thanks, > Tadeusz >
On 5/16/22 16:31, Namjae Jeon wrote: >>> Looks good. >>> And it seems that WARN_ON() is no longer needed. >> Right. Do you want me to send a follow up patch that drops the WARN_ONs? > You don't need to do it. I have applied this patch to #exfat dev > branch after removing it. > Note that I have combined 1/2 into 2/2 patch. > Thanks! That's fine with me. Thanks for taking it.
diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c index 03f142307174..92f5b5b5a0d0 100644 --- a/fs/exfat/balloc.c +++ b/fs/exfat/balloc.c @@ -149,6 +149,9 @@ int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync) struct exfat_sb_info *sbi = EXFAT_SB(sb); WARN_ON(clu < EXFAT_FIRST_CLUSTER); + if (!is_valid_cluster(sbi, clu)) + return -EINVAL; + ent_idx = CLUSTER_TO_BITMAP_ENT(clu); i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx); b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx); @@ -167,6 +170,9 @@ void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync) struct exfat_mount_options *opts = &sbi->options; WARN_ON(clu < EXFAT_FIRST_CLUSTER); + if (!is_valid_cluster(sbi, clu)) + return; + ent_idx = CLUSTER_TO_BITMAP_ENT(clu); i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx); b = BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent_idx);
Syzbot reported slab-out-of-bounds read in exfat_clear_bitmap. This was triggered by reproducer calling truncute with size 0, which causes the following trace: BUG: KASAN: slab-out-of-bounds in exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174 Read of size 8 at addr ffff888115aa9508 by task syz-executor251/365 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3c0 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 exfat_clear_bitmap+0x147/0x490 fs/exfat/balloc.c:174 exfat_free_cluster+0x25a/0x4a0 fs/exfat/fatent.c:181 __exfat_truncate+0x99e/0xe00 fs/exfat/file.c:217 exfat_truncate+0x11b/0x4f0 fs/exfat/file.c:243 exfat_setattr+0xa03/0xd40 fs/exfat/file.c:339 notify_change+0xb76/0xe10 fs/attr.c:336 do_truncate+0x1ea/0x2d0 fs/open.c:65 Add checks to validate if cluster number is within valid range in exfat_clear_bitmap() and exfat_set_bitmap() Cc: Namjae Jeon <linkinjeon@kernel.org> Cc: Sungjong Seo <sj1557.seo@samsung.com> Cc: linux-fsdevel@vger.kernel.org Cc: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org Link: https://syzkaller.appspot.com/bug?id=50381fc73821ecae743b8cf24b4c9a04776f767c Reported-by: syzbot+a4087e40b9c13aad7892@syzkaller.appspotmail.com Fixes: 1e49a94cf707 ("exfat: add bitmap operations") Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org> --- v2: - Use is_valid_cluster() helper to validate clu --- fs/exfat/balloc.c | 6 ++++++ 1 file changed, 6 insertions(+)