Created attachment 7747 [details] simple test program man 5 fstab states that if the fifth field (fs_freq) and the sixth field (fs_passno) is not present a value of zero is returned (i.q. fs_req=0,fs_passno=0 if there is no fifth and sixth field in /etc/fstab line). If fourth field ends with '\n' all work fine. But if there is extra tabs or spaces getmntent() returns garbage in ((struct mntent *) mp)->mnt_passno. It is because in misc/mntent_r.c:__getmntent_r() at line 167 no checks that sscanf() returns EOF or no striping for spaces and tabs like it done at line 164 for example. In my mashine attached test_mntent (for testtab which also attached) say: mnt_dir=/home mnt_freq=42 mnt_passno=666 mnt_dir=/home mnt_freq=42 mnt_passno=666 but must: mnt_dir=/home mnt_freq=42 mnt_passno=666 mnt_dir=/home mnt_freq=0 mnt_passno=0
Created attachment 7748 [details] test fstab
this was discussed here: https://sourceware.org/ml/libc-alpha/2014-08/msg00476.html https://sourceware.org/ml/libc-alpha/2014-10/msg00035.html https://sourceware.org/ml/libc-alpha/2014-12/msg00225.html https://sourceware.org/ml/libc-alpha/2015-01/msg00109.html and merged here: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=fb87ee96d7dd0714d52004e4676629f8d9db732f
This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "GNU C Library master sources". The branch, master has been updated via b0e805fa0d6fea33745952df7b7f5442ca4c374f (commit) from 30da407eca459329e060d0412c3fa6710f657e83 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b0e805fa0d6fea33745952df7b7f5442ca4c374f commit b0e805fa0d6fea33745952df7b7f5442ca4c374f Author: Mike Frysinger <vapier@gentoo.org> Date: Fri Aug 28 17:08:49 2015 -0400 getmntent: fix memory corruption w/blank lines [BZ #18887] The fix for BZ #17273 introduced a single byte of memory corruption when the line is entirely blank. It would walk back past the start of the buffer if the heap happened to be 0x20 or 0x09 and then write a NUL byte. buffer = '\n'; end_ptr = buffer; while (end_ptr[-1] == ' ' || end_ptr[-1] == '\t') end_ptr--; *end_ptr = '\0'; Fix that and rework the tests. Adding the testcase for BZ #17273 to the existing \040 parser does not really make sense as it's unrelated, and leads to confusing behavior: it implicitly relies on the new entry being longer than the previous entry (since it just rewinds the FILE*). Split it out into its own dedicated testcase instead. ----------------------------------------------------------------------- Summary of changes: ChangeLog | 10 +++++ misc/Makefile | 3 +- misc/mntent_r.c | 4 +- .../tst-mntent-blank-corrupt.c | 43 ++++++++----------- .../tst-mntent-blank-passno.c | 40 ++++++++++-------- misc/tst-mntent.c | 20 --------- 6 files changed, 55 insertions(+), 65 deletions(-) copy posix/bug-regex35.c => misc/tst-mntent-blank-corrupt.c (60%) copy math/tst-definitions.c => misc/tst-mntent-blank-passno.c (55%)
This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "GNU C Library master sources". The branch, release/2.21/master has been updated via f2cdbadd8a078482d3b9fc2b59e888c64cc4efae (commit) from 978908245b2c0f759100708a9966649f7b273664 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=f2cdbadd8a078482d3b9fc2b59e888c64cc4efae commit f2cdbadd8a078482d3b9fc2b59e888c64cc4efae Author: Mike Frysinger <vapier@gentoo.org> Date: Fri Aug 28 17:08:49 2015 -0400 getmntent: fix memory corruption w/blank lines [BZ #18887] The fix for BZ #17273 introduced a single byte of memory corruption when the line is entirely blank. It would walk back past the start of the buffer if the heap happened to be 0x20 or 0x09 and then write a NUL byte. buffer = '\n'; end_ptr = buffer; while (end_ptr[-1] == ' ' || end_ptr[-1] == '\t') end_ptr--; *end_ptr = '\0'; Fix that and rework the tests. Adding the testcase for BZ #17273 to the existing \040 parser does not really make sense as it's unrelated, and leads to confusing behavior: it implicitly relies on the new entry being longer than the previous entry (since it just rewinds the FILE*). Split it out into its own dedicated testcase instead. (cherry picked from commit b0e805fa0d6fea33745952df7b7f5442ca4c374f) ----------------------------------------------------------------------- Summary of changes: ChangeLog | 10 +++++ NEWS | 2 +- misc/Makefile | 3 +- misc/mntent_r.c | 4 +- .../tst-mntent-blank-corrupt.c | 27 +++++++------ .../tst-mntent-blank-passno.c | 40 +++++++++++--------- misc/tst-mntent.c | 20 ---------- 7 files changed, 53 insertions(+), 53 deletions(-) copy libio/test-fmemopen.c => misc/tst-mntent-blank-corrupt.c (60%) copy math/tst-definitions.c => misc/tst-mntent-blank-passno.c (55%)
This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "GNU C Library master sources". The branch, release/2.22/master has been updated via 3007f797a1a596e954f44879a5a7267966186ba4 (commit) from 64c25345714d792b283c8c8469d58f898d1ef109 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=3007f797a1a596e954f44879a5a7267966186ba4 commit 3007f797a1a596e954f44879a5a7267966186ba4 Author: Mike Frysinger <vapier@gentoo.org> Date: Fri Aug 28 17:08:49 2015 -0400 getmntent: fix memory corruption w/blank lines [BZ #18887] The fix for BZ #17273 introduced a single byte of memory corruption when the line is entirely blank. It would walk back past the start of the buffer if the heap happened to be 0x20 or 0x09 and then write a NUL byte. buffer = '\n'; end_ptr = buffer; while (end_ptr[-1] == ' ' || end_ptr[-1] == '\t') end_ptr--; *end_ptr = '\0'; Fix that and rework the tests. Adding the testcase for BZ #17273 to the existing \040 parser does not really make sense as it's unrelated, and leads to confusing behavior: it implicitly relies on the new entry being longer than the previous entry (since it just rewinds the FILE*). Split it out into its own dedicated testcase instead. (cherry picked from commit b0e805fa0d6fea33745952df7b7f5442ca4c374f) ----------------------------------------------------------------------- Summary of changes: ChangeLog | 10 +++++ NEWS | 2 +- misc/Makefile | 3 +- misc/mntent_r.c | 4 +- .../tst-mntent-blank-corrupt.c | 43 ++++++++----------- .../tst-mntent-blank-passno.c | 40 ++++++++++-------- misc/tst-mntent.c | 20 --------- 7 files changed, 56 insertions(+), 66 deletions(-) copy posix/bug-regex35.c => misc/tst-mntent-blank-corrupt.c (60%) copy math/tst-definitions.c => misc/tst-mntent-blank-passno.c (55%)
This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "GNU C Library master sources". The branch, gentoo/2.21 has been updated via 460e5da421067eb690ba3b9d11183c4b7db37e4f (commit) from 43d7ce9238c59c61003994cb26eff4a6a072ebd5 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=460e5da421067eb690ba3b9d11183c4b7db37e4f commit 460e5da421067eb690ba3b9d11183c4b7db37e4f Author: Mike Frysinger <vapier@gentoo.org> Date: Fri Aug 28 17:08:49 2015 -0400 getmntent: fix memory corruption w/blank lines [BZ #18887] The fix for BZ #17273 introduced a single byte of memory corruption when the line is entirely blank. It would walk back past the start of the buffer if the heap happened to be 0x20 or 0x09 and then write a NUL byte. buffer = '\n'; end_ptr = buffer; while (end_ptr[-1] == ' ' || end_ptr[-1] == '\t') end_ptr--; *end_ptr = '\0'; Fix that and rework the tests. Adding the testcase for BZ #17273 to the existing \040 parser does not really make sense as it's unrelated, and leads to confusing behavior: it implicitly relies on the new entry being longer than the previous entry (since it just rewinds the FILE*). Split it out into its own dedicated testcase instead. (cherry picked from commit b0e805fa0d6fea33745952df7b7f5442ca4c374f) (cherry picked from commit f2cdbadd8a078482d3b9fc2b59e888c64cc4efae) ----------------------------------------------------------------------- Summary of changes: misc/Makefile | 3 +- misc/mntent_r.c | 4 +- .../tst-mntent-blank-corrupt.c | 27 +++++++------ .../tst-mntent-blank-passno.c | 40 +++++++++++--------- misc/tst-mntent.c | 20 ---------- 5 files changed, 42 insertions(+), 52 deletions(-) copy libio/test-fmemopen.c => misc/tst-mntent-blank-corrupt.c (60%) copy math/tst-definitions.c => misc/tst-mntent-blank-passno.c (55%)
This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "GNU C Library master sources". The branch, gentoo/2.22 has been updated via ca6a9ce6151759981cc2efd58e053148c7db2fea (commit) from 0acbb93ebb8cf2a646cc2b685cd13b22d52f1e27 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=ca6a9ce6151759981cc2efd58e053148c7db2fea commit ca6a9ce6151759981cc2efd58e053148c7db2fea Author: Mike Frysinger <vapier@gentoo.org> Date: Fri Aug 28 17:08:49 2015 -0400 getmntent: fix memory corruption w/blank lines [BZ #18887] The fix for BZ #17273 introduced a single byte of memory corruption when the line is entirely blank. It would walk back past the start of the buffer if the heap happened to be 0x20 or 0x09 and then write a NUL byte. buffer = '\n'; end_ptr = buffer; while (end_ptr[-1] == ' ' || end_ptr[-1] == '\t') end_ptr--; *end_ptr = '\0'; Fix that and rework the tests. Adding the testcase for BZ #17273 to the existing \040 parser does not really make sense as it's unrelated, and leads to confusing behavior: it implicitly relies on the new entry being longer than the previous entry (since it just rewinds the FILE*). Split it out into its own dedicated testcase instead. (cherry picked from commit b0e805fa0d6fea33745952df7b7f5442ca4c374f) (cherry picked from commit 3007f797a1a596e954f44879a5a7267966186ba4) ----------------------------------------------------------------------- Summary of changes: misc/Makefile | 3 +- misc/mntent_r.c | 4 +- .../tst-mntent-blank-corrupt.c | 43 ++++++++----------- .../tst-mntent-blank-passno.c | 40 ++++++++++-------- misc/tst-mntent.c | 20 --------- 5 files changed, 45 insertions(+), 65 deletions(-) copy posix/bug-regex35.c => misc/tst-mntent-blank-corrupt.c (60%) copy math/tst-definitions.c => misc/tst-mntent-blank-passno.c (55%)